include/linux/node.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * include/linux/node.h - generic node definition
   4  *
   5  * This is mainly for topological representation. We define the
   6  * basic 'struct node' here, which can be embedded in per-arch
   7  * definitions of processors.
   8  *
   9  * Basic handling of the devices is done in drivers/base/node.c
  10  * and system devices are handled in drivers/base/sys.c.
  11  *
  12  * Nodes are exported via driverfs in the class/node/devices/
  13  * directory.
  14  */
  15 #ifndef _LINUX_NODE_H_
  16 #define _LINUX_NODE_H_
  17
  18 #include <linux/device.h>
  19 #include <linux/cpumask.h>
  20 #include <linux/list.h>
  21 #include <linux/workqueue.h>
  22
  23 /**
  24  * struct node_hmem_attrs - heterogeneous memory performance attributes
  25  *
  26  * @read_bandwidth:     Read bandwidth in MB/s
  27  * @write_bandwidth:    Write bandwidth in MB/s
  28  * @read_latency:       Read latency in nanoseconds
  29  * @write_latency:      Write latency in nanoseconds
  30  */
  31 struct node_hmem_attrs {
  32         unsigned int read_bandwidth;
  33         unsigned int write_bandwidth;
  34         unsigned int read_latency;
  35         unsigned int write_latency;
  36 };
  37
  38 enum cache_indexing {
  39         NODE_CACHE_DIRECT_MAP,
  40         NODE_CACHE_INDEXED,
  41         NODE_CACHE_OTHER,
  42 };
  43
  44 enum cache_write_policy {
  45         NODE_CACHE_WRITE_BACK,
  46         NODE_CACHE_WRITE_THROUGH,
  47         NODE_CACHE_WRITE_OTHER,
  48 };
  49
  50 /**
  51  * struct node_cache_attrs - system memory caching attributes
  52  *
  53  * @indexing:           The ways memory blocks may be placed in cache
  54  * @write_policy:       Write back or write through policy
  55  * @size:               Total size of cache in bytes
  56  * @line_size:          Number of bytes fetched on a cache miss
  57  * @level:              The cache hierarchy level
  58  */
  59 struct node_cache_attrs {
  60         enum cache_indexing indexing;
  61         enum cache_write_policy write_policy;
  62         u64 size;
  63         u16 line_size;
  64         u8 level;
  65 };
  66
  67 #ifdef CONFIG_HMEM_REPORTING
  68 void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs);
  69 void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
  70                          unsigned access);
  71 #else
  72 static inline void node_add_cache(unsigned int nid,
  73                                   struct node_cache_attrs *cache_attrs)
  74 {
  75 }
  76
  77 static inline void node_set_perf_attrs(unsigned int nid,
  78                                        struct node_hmem_attrs *hmem_attrs,
  79                                        unsigned access)
  80 {
  81 }
  82 #endif
  83
  84 struct node {
  85         struct device   dev;
  86         struct list_head access_list;
  87
  88 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
  89         struct work_struct      node_work;
  90 #endif
  91 #ifdef CONFIG_HMEM_REPORTING
  92         struct list_head cache_attrs;
  93         struct device *cache_dev;
  94 #endif
  95 };
  96
  97 struct memory_block;
  98 extern struct node *node_devices[];
  99 typedef  void (*node_registration_func_t)(struct node *);
 100
 101 #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_NUMA)
 102 extern int link_mem_sections(int nid, unsigned long start_pfn,
 103                              unsigned long end_pfn);
 104 #else
 105 static inline int link_mem_sections(int nid, unsigned long start_pfn,
 106                                     unsigned long end_pfn)
 107 {
 108         return 0;
 109 }
 110 #endif
 111
 112 extern void unregister_node(struct node *node);
 113 #ifdef CONFIG_NUMA
 114 /* Core of the node registration - only memory hotplug should use this */
 115 extern int __register_one_node(int nid);
 116
 117 /* Registers an online node */
 118 static inline int register_one_node(int nid)
 119 {
 120         int error = 0;
 121
 122         if (node_online(nid)) {
 123                 struct pglist_data *pgdat = NODE_DATA(nid);
 124                 unsigned long start_pfn = pgdat->node_start_pfn;
 125                 unsigned long end_pfn = start_pfn + pgdat->node_spanned_pages;
 126
 127                 error = __register_one_node(nid);
 128                 if (error)
 129                         return error;
 130                 /* link memory sections under this node */
 131                 error = link_mem_sections(nid, start_pfn, end_pfn);
 132         }
 133
 134         return error;
 135 }
 136
 137 extern void unregister_one_node(int nid);
 138 extern int register_cpu_under_node(unsigned int cpu, unsigned int nid);
 139 extern int unregister_cpu_under_node(unsigned int cpu, unsigned int nid);
 140 extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
 141
 142 extern int register_memory_node_under_compute_node(unsigned int mem_nid,
 143                                                    unsigned int cpu_nid,
 144                                                    unsigned access);
 145
 146 #ifdef CONFIG_HUGETLBFS
 147 extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
 148                                          node_registration_func_t unregister);
 149 #endif
 150 #else
 151 static inline int __register_one_node(int nid)
 152 {
 153         return 0;
 154 }
 155 static inline int register_one_node(int nid)
 156 {
 157         return 0;
 158 }
 159 static inline int unregister_one_node(int nid)
 160 {
 161         return 0;
 162 }
 163 static inline int register_cpu_under_node(unsigned int cpu, unsigned int nid)
 164 {
 165         return 0;
 166 }
 167 static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 168 {
 169         return 0;
 170 }
 171 static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 172 {
 173 }
 174
 175 static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
 176                                                 node_registration_func_t unreg)
 177 {
 178 }
 179 #endif
 180
 181 #define to_node(device) container_of(device, struct node, dev)
 182
 183 #endif /* _LINUX_NODE_H_ */